Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/b743db091d25
Author: Eitan Isaacson <eitan@monotonous.org>
Desc: Merge pull request #25151 from eeejay/bug-1069628

Bug 1069628 - Introduce sound for end-of-page in screen reader. r=alive

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https://hg.mozilla.org/integration/gaia-central/rev/cfc5cbf068c6
Author: Eitan Isaacson <eitan@monotonous.org>
Desc: Bug 1069628 - Introduce sound for end-of-page in screen reader.
Bumping manifests a=b2g-bump